Methodology for treating biomass, coal, msw/any kind of wastes and sludges from sewage treatment plants to produce clean/upgraded materials for the production of hydrogen, energy and liquid fuels-chemicals

ABSTRACT

The present invention refers to a method for treating agricultural or forestry or urban origin biomass or mixture of different origin&#39;s biomass feedstocks, low quality coal such as peat, lignite or subbituminous or/and bituminous coal, or/and mixtures of them, garbage and urban/industrial wastes, solid and/or liquid state, as well as sewage treatment plant sludges by means of removal of inorganic elements, such as silica, potassium, sodium, chlorine, sulfur, phosphorus, nitrogen and heavy metals such as zinc, mercury, copper, lead, chromium, etc., and the addition of new inorganic elements such as calcium, magnesium, titanium, zirconium, yttrium, aluminum and ammonium, in order to produce a purified and upgraded solid and/or liquid material which can be used as raw material in thermochemical conversion processes such as combustion, flash (t&lt;1 sec)/fast pyrolysis (1&lt;t&lt;10 sec), as well as in the gasification for the production of energy, and/or hydrogen-rich gas and liquid hydrocarbons.

The present invention refers to a method for treating agricultural orforestry or urban origin biomass or mixture of different origin'sbiomass feedstocks, low quality coal such as peat, lignite orsubbituminous or/and bituminous coal, or/and mixtures of them, garbageand urban/industrial wastes, solid and/or liquid state, as well assewage treatment plant sludges by means of removal of inorganicelements, such as silica, potassium, sodium, chlorine, sulfur,phosphorus, nitrogen and heavy metals such as zinc, mercury, copper,lead, chromium, etc., and the addition of new inorganic elements such ascalcium, magnesium, titanium, zirconium, yttrium, aluminum and ammonium,in order to produce a purified and upgraded solid and/or liquid materialwhich can be used as raw material in thermochemical conversion processessuch as combustion, flash (t<1 sec)/fast pyrolysis (1<t<10 sec), as wellas in the gasification for the production of energy, and/orhydrogen-rich gas and liquid hydrocarbons which can be further upgradedby applying commercially available thermochemical conversiontechnologies for the production of pure hydrogen, liquid fuels,chemicals and energy with great economic and environmental benefits.

The excessive use of fossil fuels such as coal, oil and natural gasnowadays for energy/heat production as well as liquid and solid/gaseoustransportation fuels causes major environmental problems such asemissions of sulfur and nitrogen oxides, particulates, heavy metals,methane and carbon dioxide. Additionally, the mining processes causepollution of the local environment and especially of water, air andsoil.

Aiming to reduce the gaseous/liquid and solid emissions caused by theuse of conventional fuels and especially to reduce emissions of gasesthat contribute to the greenhouse effect, the use of renewable energysources such as wind, solar, hydro and biomass is encouraged. Especiallythe use of biomass in solid and liquid form to produce liquid andgaseous biofuels which will not contribute to the greenhouse effect ishighly important for solving that problem.

In addition, the recycling and recovery of urban and/or industrial wasteand municipal waste such as garbage, wastewater treatment sludges, etc.,is nowadays one of the biggest environmental problems worldwide. Everyyear, millions of tons of waste require safe as well as economicallyviable disposal and recovery. The most common disposal method is storingwastes in dumps followed by incineration and recycling to produce newmaterials. However, the high content of garbage and wastes in alkalimetals, chlorine, sulfur and heavy metals make their thermochemicalapplication problematic, costly and very low efficient.

The problems caused nowadays during the thermochemical incineration,combustion, gasification and pyrolysis of biomass is due to the ashcomposition. These problems occur especially when biomass derived fromagricultural, forest and urban environment such as various kinds ofstraw, different kinds of waste from agricultural industries such ascotton, peanut olive, etc., as well as from trimmings and wood residuesfrom construction and furniture production. Similar problems occur whenyou use low-quality coal such as peat, lignite andsubbituminous/bituminous coal, used mainly for power and/or heatgeneration on a large scale, as well as urban and industrial originwastes and wastewater treatment sludges which are intended to be usedfor safe, economically viable and environmentally beneficialtreatment/deactivation/deposition. The ash of these specific biomasstypes is very rich in alkali metals, chlorine, sulfur and phosphorus,therefore the gases, liquids and solids produced during thethermochemical conversion of that biomass types tend to react with eachother and with any other inorganic compounds present during theconversion, as well as with the metal surfaces creating corrosionproblems, deposits and agglomerates. They also generate emissions whichresult in great financial losses, environmental problems and in theinability to use certain types of biomass on a large scale, separateand/or combined with solid or gaseous fuels for power generation, liquidfuels and chemicals production. Similarly, the ash of many low-qualitycoal fuels such as peat, lignite and subbituminous/bituminous coalappears to be also rich in alkali metals, chlorine and sulfur, where theash composition differs depending on the coal quality and the specificcharacteristics of each coal deposit.

Consequently, similar problems, although of lower intensity compared towith biomass use, are observed, which lead to financial losses,environmental problems, and limited efficiency in the use of such coals,as well as to problems in their application as in the case ofgasification of lignite with high sodium and chloride content for energyand/or liquid fuels production.

Additionally, the remaining ash from urban and industrial origin wastesand wastewater treatment sludges is rich in alkali metals, chlorine,sulfur, and phosphorus as well as in heavy metals such as zinc, lead,copper, chromium etc., which makes their thermochemical applicationproblematic, costly and very low efficient.

Moreover, the existence of large amounts of chlorine in the structure ofpolymers/plastics such as polyvinyl chloride (PVC), which is present ina large amount of plastics included in solid wastes, results in theproduction of large quantities of dioxins (PCDD) and furans (PCDF),which are not only harmful for human health but also for other forms oflife. The removal/destruction of these pollutants before being emittedto the environment requires the use of very expensive technologies ofhigh accident risk.

Solving these problems will result in further use of biomass, urban andindustrial origin wastes both in solid and liquid form and wastewatertreatment sludges for the production of energy, liquid fuels andchemicals as well as for the economic and efficient use of coal withmajor economic and environmental benefits especially nowadays when theimported energy cost appears to be rising and greenhouse gases fromsolid fuels should be reduced. The increased use of biomass or/and urbanand industrial origin wastes as well as the more efficient use oflow-quality coals used on a general basis for energy production areexpected to contribute decisively not only to the reduction ofgreenhouse gases and to the emission of sulfur oxides, nitrogen, heavymetals and particles that pollute the environment and human health, butalso in the cost reduction of energy and fuel production.

The currently applied techniques and methods dealing with these problemsappear to have only limited success and, as a consequence, the use ofbiomass in thermochemical conversion appears to be, worldwide, verylimited, and restricted mainly in feedstocks like wood which presentsfewer problems. As far as the use of low-quality coals is concerned, thespecific problems limit their thermochemical conversion efficiency andlead to the use of larger amounts of feedstocks for the production ofenergy and fuels/chemicals, causing the increase on greenhouse gasemissions and the financially non-efficient exploitation of the coaldeposits with larger content of alkali metals, chlorine and sulphur.Various pretreatment technologies have been proposed to reduce theproblems caused by the thermochemical conversion of coal, biomass andwaste but they have limited success with disproportionately high costsand they all fail to control and eliminate effectively all thosedifferent factors such as silicon, alkali metals, chlorine, sulfur,phosphorus, heavy metals, nitrogen, etc. that lead to the aforementionedproblems. Examples of such methodologies which put a limit on the aboveproblems are described in: Bender (U.S. Pat. No. 4,560,390), McMahon(U.S. Pat. No. 4,304,571), Grant (U.S. Pat. No. 4,137,050).

The purpose of this invention is to achieve the upgrading andpurification of agro/forest/urban origin biomass or mixture of biomassesof different origins, low quality coal such as peat, lignite orsubbituminous and/or bituminous coal, or mixtures of them, urban andindustrial origin wastes and wastewater treatment sludges by removingthe harmful inorganic elements such as silicon, sodium, potassium,chlorine, sulfur, phosphorus, nitrogen and heavy metals such as cadmium,chromium, nickel, lead, mercury, arsenic etc., and/or by deactivatingthem so that they do not adversely affect the thermochemical conversionprocesses such as combustion, flash/fast pyrolysis and gasificationwhich are used to produce energy and/or gaseous/liquid hydrocarbons incase of pyrolysis and gas in case of gasification, which can be used forthe production of pure hydrogen and/or liquid fuels/chemicals havingzero footprint regarding greenhouse gas emissions and high financialvalue.

The invention is able to minimize/eliminate corrosion problems,deposition, ash agglomeration, and gaseous emissions (potassium, sodium,chlorine, sulfur, nitrogen and phosphorus), heavy metals (Cu, Pb, Zn,Cr, Hg, As, Mo, etc.), dioxins and furans (PCDD, PCDF) duringthermochemical incineration, combustion, gasification, pyrolysis of theraw material used, e.g. agro/forest/urban origin biomass or biomassmixtures of different origins, coal or coal mixtures of differentorigins, low quality coal such as peat, lignite orsubbituminous/bituminous coal, garbage and urban/industrial wastes,solid and/or liquid state, as well as sewage treatment plant sludges.

The invention is defined in independent claim 1. Features of thedependent claims add further advantages to the invention.

The intended purpose as surprisingly found in the laboratory is achievedby leaching of agro/forest/urban origin biomass or biomass mixtures ofdifferent origins, coal or coal mixtures of different origins, lowquality coal such as peat, lignite or subbituminous/bituminous coal, ormixtures of them, garbage and urban/industrial wastes, as well as sewagetreatment plant sludges with aqueous solutions of inorganic and/ororganic salts and bases under pressure using the reactor depicted inFIG. 1. Mixtures of both organic and inorganic acids/salts can be usedin the process to achieve the desired result considering that theproportion of acid is limited to less than 30% of the total mixture on aweight basis and preferably the extent of which does not lead to thecreation of acidic conditions having a pH less than 5 in the solutionunder pressure.

The novelty of this invention is based on the fact that it's the firsttime when the simultaneous removal of all harmful inorganic elements(Si, K, Na, P, Cl, S, heavy metals, nitrogen) and/or their deactivationis possible to such a large extent that the resulting upgraded/cleansolid and liquid materials are able to be used in thermochemicalconversion processes (combustion, gasification, pyrolysis) withoutemissions, corrosion, deposition, etc. problems at the lowest possiblecost and greater energy efficiency and financial benefit.

As surprisingly found in the laboratory, the combined use of theinnovative reactor illustrated in FIG. 1 with the appropriate appliedconditions and inorganic/organic compounds can lead to the desiredresults. Although different commercially available pressurized reactorscould also be used for the pretreatment, only the reactor in FIG. 1ensures the highest possible process efficiency by carrying out thepretreatment in an integrated two-step process demonstrating the maximumefficiency at the lowest cost, whereas commercial reactors require twoseparate processes using separate reactors.

As depicted in FIG. 1, the high pressure reactor consists of twoseparate reactors in a parallel mode. Each reactor contains an initialpressurized vessel where the raw material and the aqueous solution aremixed under ambient temperature and pressure having materiaVaqueousphase ratio from 15 grams per liter up to 800 grams per liter andsolvent concentration of 0.5-1.5% weight basis depending on the materialused. This does not prevent the application of higher concentrations orreaction times considering that this achieves a better or differentresult. Consequently, if the material treatment targets the siliconstructural removal during the first reaction step, the pressure vesselwith aqueous alkali solution (base and/or salt) such as sodium,potassium, is heated between 110-150° C. and pressure 2-10 atm if thematerial is biomass while at temperatures from 130° C. up to 195° C. andpressure 4-20 atm if the treated material is coal, garbage/waste forless than five minutes in case of biomass and less than 20 minutes incase of coal, garbage/waste. As shown in FIG. 1, each pressurized vesselis equipped with a direct discharge valve which communicates with theinterior of the reactor via a pipeline at the end of which there is a 40micron diameter solids filter. The immediate depressurization caused bythe discharge valve opening after the end of the treatment processresults in solid/liquid separation letting the liquid to be concentratedand cooled in the recover tank before being recycled into the process asshown in FIG. 1 while the solid product is removed in the second phaseand is transferred to the second pressurized vessel by opening the valveof the pressurized reactor's bottom.

Simultaneously, the parallel reactor operates one step back from theinitial reactor in order to realize a process which is semi-batch but inprogress at any time.

When the material reaches the second compartment of the pressurizedreactor, the second pretreatment stage takes place. This step includesthe leaching of the material with an aqueous solution of inorganicand/or organic salts. Mixtures of both organic and inorganic acids/saltscan be used in the process to achieve the desired effect while theproportion of acid is limited to less than 30% of the total mixture on aweight basis and preferably to such an extent that will not createacidic conditions of pH less than 5 in the pressurized solution. Theprocess conditions are temperature between 110-160° C. and pressure 2-10atm if the material is biomass, temperature between 140-195° C. andpressure 4-20 atm if the treated material is coal, garbage/waste whilepressure 4-45 atm and temperature (140-245° C.) in case ofplastics/polymer materials especially if they have a chlorine containingstructure, for less than 5 minutes in case of biomass and less than 20minutes in case of coal, garbage/waste and plastics/polymer materials.Regarding organic and/or inorganic compounds, they are/can be used anywater-soluble organic/inorganic salts of calcium, magnesium, titanium,zirconium, yttrium, aluminum and ammonium in proportions of 0.07% up to4% weight basis in aqueous solution depending on the type of the treatedmaterial. In case of biomass, solvent concentration can be reduced to0.5-1.5% and in case of coal and garbage/waste typically ranges between0.5-4%. Additionally, all organic and/or inorganic acids that createwater-soluble salts with the aforementioned cations can also be used.The acids concentration when acids/salt mixtures are applied issufficiently low so that the pH of the solution is always higher than 5,preferably 6.5. Although the use of higher concentrations of salts inthe solutions is feasible, it is not considered as necessary to achievethe desired result. After the end of the process, the solid-liquidseparation as well as the solid removal from the pressurized reactortakes place in the same way as previously described and as shown in FIG.1 which illustrates the process.

The conditions inside the pressurized reactor are always slightlyacidic/neutraValkaline depending on the use of suitable solvents aspreviously described. This fact combined with the low pressure (2-10atm) and temperatures (110-168° C.) in case of biomass, pressures (2-20atm) and temperatures (110-195° C.) in case of coal/garbage/waste andpressures (4-45 atm) and temperatures (140-245° C.) in case ofplastics/polymer materials especially when they contain structuralchlorine, results in the use of much cheaper materials such as carbonsteel for manufacturing the pressurized reactors so that the processcost, both capital and operating, appears to be reduced by 50-80%compared to reactors that use much higher temperatures and pressureswhile their operating conditions are mildly to strongly acidic.

The pre-treatment consists of two stages in case of coal as well asbiomass/garbage/waste whose ash contains silicon in large percentusually above 10% SiO₂ in ash basis, which should be removed in order toreduce deposition problems, ash production and to create new high-valuematerials such as pure silicon. In any case and if necessary, materialshaving less silicon content in the ash can be used for upgrading. Inthat case, the first pretreatment stage is to remove the silicon fromthe treated material. This reaction is carried out at temperaturesbetween 110-150° C. and pressure 2-10 atm when the material is biomasswhile at 130-195° C., pressure 4-20 atm when the material is coal and/orgarbage/waste so that the aqueous phase remains in liquid form and isnot converted to gas. Although higher temperatures (200-350° C.) andpressures could be used, the financial cost of such an option combinedwith the small additional benefits for the process itself, make such achoice unprofitable. This leaching process is performed by using aqueoussolutions of strong bases and/or salts of strong bases such aspotassium, sodium. This does not prevent the use of other activeingredients bringing the same result. The reaction time is now limitedbelow 5 minutes in case of biomass while in case of coal, waste, etc.materials the treatment time ranges from 5 to 20 minutes, thesolid/aqueous phase ratio can range from 15 grams per liter to 800 gramsper liter depending on the treated material where the highersolid/liquid ratio is observed in case of coal and waste/litter, and thesolution concentration of strong bases and/or salts of strong basesbelow 1.5% weight basis where better results are obtained forconcentrations of 0.5-1% weight basis. This does not prevent theapplication of higher concentrations or reaction times if it isconsidered to achieve a better or different result. This process leadsto the reaction of silicon with the strong alkali forming a watersoluble alkali compound such as the KSiO₃ while removing silica from thetreated material by over 80% and up to 100% applying the appropriateconditions. Simultaneously, short residence and reaction time limit thereaction of alkali metal with the organic phase of the material andconsequently the material loss. The treated material is initially sizereduced using appropriate equipment so that the size of the treatedparticles are limited below 5 mm and preferably less than 2 mm, althoughlarger particle sizes can be used if the pretreatment conditions aremodified.

After the end of the first pretreatment stage, the resulting materialhas increased concentration of alkali metals and minimum siliconcontent. The removal of the liquid phase from the solid one and thesolid transfer from the first to the second pressurized compartment isdescribed in the operating principle of the pressurized reactor. Theremoved liquid is recycled to the process several times until it issaturated in silicates. Then it is further processed for collecting thesilicon dioxide which is a high value material and can be used toproduce pure silicon by applying commercially available methods.

In the second pressurized compartment, the material is now washed withan aqueous solution of inorganic and/or organic salts. Mixtures of bothorganic and inorganic acids/salts can also be used in the process toachieve the desired result considering that the proportion of acid islimited to less than 30% of the total mixture on a weight basis andpreferably the extent of which does not lead to the creation of acidicconditions having a pH less than 5 in the pressurized solution.

Regarding organic and/or inorganic compounds, they are/can be used anywater-soluble organic/inorganic salts of calcium, magnesium, titanium,zirconium, yttrium, aluminum and fluoride in proportions of 0.07% up to4% weight basis in aqueous solution depending on the type of the treatedmaterial. In case of biomass, solvent concentration can be reduced to0.5-1.5% and in case of coal and garbage/waste typically ranges between0.5-4%. Additionally, all organic and/or inorganic acids that createwater-soluble salts with the aforementioned cations can also be used.The acids concentration when acids/salt mixtures are applied issufficiently low so that the pH of the solution is always higher than 5,preferably 6.5. Although the use of higher concentrations of salts inthe solutions is feasible, it is not considered as necessary to achievethe desired result.

Examples are salts of calcium acetate/citrate/nitrate and/or magnesiumacetate/citrate/nitrate and/or ammonium acetate/citrate/nitrate. Alsoacetic acid, citric acid, nitric acid could be used. When magnesium,titanium, aluminum, yttrium, zirconium and/or ammonium salts are used,the addition of calcium salt to the mixture ranging from 1/10 up to ⅓ ofthe total salts concentration is always recommended for better results.However, the calcium salts can be used separately without the presenceof other salts.

This reaction is carried out at temperatures between 110-160° C. andpressure 2-10 atm when the material is biomass while at 140-195° C.,pressure 4-20 atm when the material is coal and/or garbage/waste so thatthe aqueous phase remains in liquid form and is not converted to gas.Although higher temperatures (200-350° C.) and pressures could be used,the financial cost of such an option combined with the small additionalbenefits for the process itself, make such a choice unprofitable. Thereaction time is now limited below 5 minutes in case of biomass while incase of coal, waste, plastic etc. materials the treatment time rangesfrom 5 to 20 minutes, the solid/aqueous phase ratio can range from 15grams per liter to 800 grams per liter depending on the treated materialwhere the higher solid/liquid ratio is observed in case of coal andwaste/litter.

The applied ratios depend on the type and composition of the pretreatedmaterial (e.g. biomass, coal, garbage/waste, etc.) as well as on thedesired properties which are going to be applied to the pretreatedmaterial. Regarding the creation of the aqueous solution, any kind ofwater from the public water system, source, etc., can be employed.During the treatment with the aqueous solution of the organic and/orinorganic solvent which is created by mixing the specific organic and/orinorganic water-soluble salts and/or acids, the alkali metals (K, Na),sulfur, phosphorus, the heavy metals (Cu, Pb, Zn, Cr, Hg, etc.) as wellas the chlorine present in the structure of the treated materials aretransferred into the aqueous phase and are removed from the pretreatedmaterial mainly as inorganic/organic salts.

Simultaneously, cations such as Ca, Mg. Al, Ti. Zr, NH₄, etc., replacehydrogen atoms and/or alkali metals and others, inside the structure ofthe treated materials thereby increasing the concentration of thesecations in the treated materials. This is concluded to have asurprisingly positive effect on the thermochemical conversion reactionssuch as combustion, flash/fast pyrolysis and gasification which favorsthe production of energy without deposition/emission problems, theproduction of purified hydrogen-rich gas, and/or pure liquid phasehydrocarbons with high conversion efficiency which can be further usedfor the production of pure hydrogen and liquid fuels/chemicals with lowfinancial cost.

After the second pretreatment stage, the clean/upgraded solid/liquid endproduct which now contains very small to zero silicon, alkali metals,phosphorous, sulfur, chlorine and heavy metals concentration as well asincreased cations concentration used in the last process step (Ca, Mg,Al, Ti, Zr, NH₄, etc.) is separated from the liquid phase in the sameway as described in the operation of the pressurized reactor, while theliquid/aqueous phase is recycled back to the process.

Purification of the liquid phase from inorganic elements such aspotassium, sodium, phosphorus, sulfur, chlorine, heavy metals is carriedout after several loops using ion exchange resins when sign ofsaturation of the aqueous solution with the specific components isoccurred.

In case that the pretreated material contains less than 10% SiO₂ ashbasis, or only silicon traces as in all kinds of plastics, RDF (refusederived fuel), etc., biomass such as peach kernels, DDGS, etc., forwhich silicon is considered that there is no reason to be removed fromthe treated material, then the material is washed with an aqueoussolution of inorganic and/or organic salts, mixtures of both organic andinorganic acids/salts considering that the proportion of acid is limitedto less than 30% of the total mixture on weight basis and preferably theextent of which does not lead to the creation of acidic conditionshaving a pH less than 5 in the pressurized solution.

In this case, both separate pressurized compartments from each parallelreactor illustrated in FIG. 1 can be used simultaneously for treatingthe material as the treatment is now carried out in one step. Thisresults in treating the double amount of material compared to theprevious case where treatment consisted of two stages. The treatment isperformed in the same way described in detail in the operationcharacteristics of the pressurized reactor. Regarding organic and/orinorganic compounds, they are/can be used any water-solubleorganic/inorganic salts of calcium, magnesium, titanium, zirconium,yttrium, aluminum and ammonium in proportions of 0.07% up to 4% weightbasis in aqueous solution depending on the type of the treated material.In case of biomass, solvent concentration can be reduced to less than1.5% while in case of coal and garbage/waste typically ranges between0.5-4%. Additionally, all organic and/or inorganic acids that createwater-soluble salts with the aforementioned cations can also be used.The acids concentration when acids/salt mixtures are applied issufficiently low so that the pH of the solution is always higher than 5,preferably 6.5. Although the use of higher concentrations of salts inthe solutions is feasible, it is not considered as necessary to achievethe desired result.

Examples are salts of calcium acetate/citrate/nitrate and/or magnesiumacetate/citrate/nitrate and/or ammonium acetate/citrate/nitrate. Alsoacetic acid, citric acid, nitric acid can be used. When magnesium,titanium, aluminum, yttrium, zirconium and/or ammonium salts are used,the addition of calcium salt to the mixture ranging from 1/10 up to ⅓ ofthe total salts concentration is always recommended for better results.However, the calcium salts can be used separately without the presenceof other salts.

This reaction is carried out at temperatures between 110-160° C. andpressure 2-10 atm when the material is biomass, between 140-195° C.,pressure 4-20 atm when the material is coal, garbage/waste, between140-245° C., pressure 4-45 atm when the material is plastic especiallywith high chlorine concentration such as poly-vinyl chloride, or othersynthetic material so that the aqueous phase remains in liquid form andis not converted to gas. Although higher temperatures (250-350° C.) andpressures could be used, the financial cost of such an option combinedwith the small additional benefits for the process itself, make such achoice unprofitable. The reaction time is now limited below 5 minutes incase of biomass while in case of coal, waste, plastic etc. materials,the treatment time ranges from 5 to 20 minutes, the solid/aqueous phaseratio can range from 15 grams per liter to 800 grams per liter dependingon the treated material where the higher solid/liquid ratio is observedin case of coal, RDF and waste/litter, longer reaction times can also beused if necessary depending on the treated material as well as on thedesired properties which are going to be applied to the pretreatedmaterial.

After the end of the pretreatment process, the clean/upgradedsolid/liquid end product which now contains very small to zero silicon,alkali metals, phosphorous, sulfur, chlorine and heavy metalsconcentration as well as increased cations concentration used in thelast process step (Ca, Mg, Al, Ti, Zr, NH₄, etc.) is separated from theliquid phase in the same way as described in the operation of thepressurized reactor, while the liquid/aqueous phase is recycled back tothe process.

Purification of the liquid phase from inorganic elements such aspotassium, sodium, phosphorus, sulfur, chlorine, heavy metals is carriedout after several loops using ion exchange resins when sign ofsaturation of the aqueous solution with the specific components isoccurred.

The following examples are presented in order to indicate the effect ofthe invention on various materials such as biomass, coal, tires.However, the implementation and results of the method are not limited bythe examples given here.

EXAMPLE 1

Wheat straw is treated at elevated pressure using the reactor shown inFIG. 1. Since this material contains a large proportion of silicon inthe ash, its pretreatment is focused in the first stage on trying toremove the silicon from the ash. In order to achieve that, the sample istreated in the first stage using sodium hydroxide in the firstcompartment of the pressurized reactor. The applied conditions are thefollowing: Temperature 147° C., pressure 5-9 atm, solid/liquid ratio 10%w/w dry basis, leaching time 4.8 minutes, solvent concentration 1% w/w,material particle size <1 mm. After the first step of pretreatment thesample is moved to the second pressurized compartment where it istreated in the second step aiming at the removal of alkali metals,phosphorus, chlorine, sulfur, as well as the deactivation of componentsremaining in the material structure after the end of the process bymeans of appropriate salts so that they will be no longer a problem forthe further thermochemical treatment of the treated material. Theapplied conditions are the following: Temperature 148° C., pressure 5-9atm. solid/liquid ratio 10% w/w dry basis, leaching time 4.9 minutes,solvent concentration 1.2% w/w and calcium chloride as solvent. Afterthe pretreatment, the sample is dried at 50° C. The final solid sampleappears to have increased ease of milling requiring 30-40% less energythan the original raw wheat straw while it favors the production ofgreater strength pellets requiring reduced energy consumption by 30-50%compared again to the original raw straw. The ash content of the finaltreated material appears to be reduced by more than 30%, the siliconconcentration appears to be reduced by 80%, while the concentrations ofchlorine and active alkali metals are practically zero. The sulfur andphosphorus concentrations appear significantly reduced by 60-70% forsulfur and from 60% up to 70% for phosphorous. At the same time, thecalcium concentration is significantly increased and is now more than60% of the treated material ash. Both raw and treated material ash isthermally treated in a high temperature oven starting from 600° C.followed by 50° C. steps. Table 2 shows the results of thermaltreatment. It is clear that the ash of the treated material appears tohave significantly increased thermal resistance while the ash meltingpoint is increased to 1550° C., from 800° C. in case of raw material.

EXAMPLE 2

Olive kernel is treated at elevated pressure using the reactor shown inFIG. 1. Since this material contains a large proportion of silicon inthe ash, its pretreatment is focused in the first stage on trying toremove the silicon from the ash. In order to achieve that, the sample istreated in the first stage using potassium hydroxide in the firstcompartment of the pressurized reactor. The applied conditions are thefollowing: Temperature 147° C., pressure 5-9 atm, solid/liquid ratio 10%w/w dry basis, leaching time 4.2 minutes, solvent concentration 0.8%w/w, material particle size <1 mm. After the first step of pretreatmentthe sample is moved to the second pressurized compartment where it istreated in the second step aiming at the removal of alkali metals,phosphorus, chlorine, sulfur, as well as the deactivation of componentsremaining in the material structure after the end of the process bymeans of appropriate salts so that they will be no longer a problem forthe further thermochemical treatment of the treated material. Theapplied conditions are the following: Temperature 138° C., pressure 5-7atm, solid/liquid ratio 15% w/w dry basis, leaching time 4.9 minutes,solvent concentration 1.2% w/w and calcium nitrate as solvent. After thepretreatment, the sample is dried at 50° C. The final solid sampleappears to have increased ease of milling requiring 30-40% less energythan the original raw olive kernel while it favors the production ofgreater strength pellets requiring reduced energy consumption by 30-50%compared again to the original raw olive kernel. The ash content of thefinal treated material appears to be reduced by more than 40%, thesilicon concentration appears to be reduced by 90%, while theconcentrations of chlorine and active alkali metals are practicallyzero. The sulfur and phosphorus concentrations appear significantlyreduced by 40% for sulfur and from 60% up to 80% for phosphorous. Theconcentration of nitrogen is reduced by 45%. At the same time, thecalcium concentration is significantly increased and is now more than60% of the treated material ash. Both raw and treated material ash isthermally treated in a high temperature oven starting from 600° C.followed by 50° C. steps. Table 2 shows the results of thermaltreatment. It is clear that the ash of the treated material appears tohave significantly increased thermal resistance while the ash meltingpoint is increased to 1450° C., from 850° C. in case of raw material.

Then both the untreated and the treated material are used in fastpyrolysis tests (t=2 sec) at 600° C. These tests showed that thematerial conversion into gaseous and liquid products was increased from80% to 93% at 600° C. after pretreatment. At the same time, although SO₂was produced in the final gaseous and liquid products during pyrolysisof the raw material, there was no presence of SO₂ in case of the treatedmaterial. Additionally, the production of liquid hydrocarbons appears tobe decreased by more than 85% in case of the treated sample while theprimary end product is a gas mixture rich in H₂, CO, CH₄, and otherhydrocarbons.

EXAMPLE 3

Coal (HSMc) from a US Mine is treated at elevated pressure using thereactor shown in FIG. 1. Since this material contains a large proportionof silicon in the ash, its pretreatment is focused in the first stage ontrying to remove the silicon from the ash. In order to achieve that, thesample is treated in the first stage using sodium hydroxide in the firstcompartment of the pressurized reactor. The applied conditions are thefollowing: Temperature 165° C., pressure 10-20 atm, solid/liquid ratio35% w/w dry basis, leaching time 19 minutes, solvent concentration 3.8%w/w, material particle size <1 mm. After the first step of pretreatmentthe sample is moved to the second pressurized compartment where it istreated in the second step aiming at the removal of alkali metals,phosphorus, chlorine, sulfur, as well as the deactivation of componentsremaining in the material structure after the end of the process bymeans of appropriate salts so that they will be no longer a problem forthe further thermochemical treatment of the treated material. Theapplied conditions are the following: Temperature 195° C., pressure18-20 atm, solid/liquid ratio 35% w/w dry basis, leaching time 20minutes, solvent concentration 4% w/w and calcium chloride as solvent.After the pretreatment, the sample is dried at 50° C. The ash content ofthe final treated material appears to be reduced by more than 35%, thesilicon concentration appears to be reduced by 70%, while theconcentrations of chlorine and active alkali metals are practicallyzero. The sulfur concentration appears to be significantly reduced by50-70%, nitrogen concentration is reduced by 55%, while theconcentration of heavy metals such as Hg, Pb, Ni, Cd, As, etc. appearsto be reduced by 60-95%. At the same time, the calcium concentration issignificantly increased and is now more than 50% of the treated materialash. Both raw and treated material ash is thermally treated in a hightemperature oven starting from 800° C. followed by 50° C. steps. Table 2shows the results of thermal treatment. It is clear that the ash of thetreated material appears to have significantly increased thermalresistance while the ash melting point is increased to 1450° C., from1300° C. in case of raw material.

Then both the untreated and the treated material are used in fastpyrolysis tests (t=2 sec) at 600° C. and 800° C. These tests showed thatthe material conversion into gaseous and liquid products was increasedfrom 41 to 75% at 600° C. and from 70 to 85% at 800° C. afterpretreatment. At the same time, although SO₂ was produced in the finalgaseous and liquid products during pyrolysis of the raw material, therewas 90% reduction in the presence of SO₂ in case of the treatedmaterial. Additionally, the production of liquid hydrocarbons appears tobe decreased by more than 80% in case of the treated sample while theprimary end product is a gas mixture rich in H₂, CO, CH₄, and otherhydrocarbons.

EXAMPLE 4

Coal (EBWM) from a US Mine is treated at elevated pressure using thereactor shown in FIG. 1. Since this material contains a large proportionof silicon in the ash, its pretreatment is focused in the first stage ontrying to remove the silicon from the ash. In order to achieve that, thesample is treated in the first stage using sodium hydroxide in the firstcompartment of the pressurized reactor. The applied conditions are thefollowing: Temperature 185° C., pressure 15-20 atm, solid/liquid ratio28% w/w dry basis, leaching time 15 minutes, solvent concentration 3%w/w, material particle size <1 mm. After the first step of pretreatmentthe sample is moved to the second pressurized compartment where it istreated in the second step aiming at the removal of alkali metals,phosphorus, chlorine, sulfur, as well as the deactivation of componentsremaining in the material structure after the end of the process bymeans of appropriate salts so that they will be no longer a problem forthe further thermochemical treatment of the treated material. Theapplied conditions are the following: Temperature 195° C., pressure18-20 atm, solid/liquid ratio 28% w/w dry basis, leaching time 15minutes, solvent concentration 2.5% w/w and calcium nitrate/calciumchloride ratio: 50/50 as solvent. After the pretreatment, the sample isdried at 50° C. The ash content of the final treated material appears tobe reduced by more than 40%, the silicon concentration appears to bereduced by 80%, while the concentrations of chlorine and active alkalimetals are practically zero. The sulfur concentration appears to besignificantly reduced by 60-70%, while the concentration of heavy metalssuch as Hg, Pb, Ni, Cd, As, etc. appears to be reduced by 60-98%. At thesame time, the calcium concentration is significantly increased and isnow more than 50% of the treated material ash. Both raw and treatedmaterial ash is thermally treated in a high temperature oven startingfrom 800° C. followed by 50° C. steps. Table 2 shows the results ofthermal treatment. It is clear that the ash of the treated materialappears to have significantly increased thermal resistance while the ashmelting point is increased to 1450° C., from 1300° C. in case of rawmaterial.

Then both the untreated and the treated material are used in fastpyrolysis tests (t=2 sec) at 600° C. and 800° C. These tests showed thatthe material conversion into gaseous and liquid products was increasedfrom 48 to 73% at 600° C. and from 65 to 80% at 800° C. afterpretreatment. At the same time, although SO₂ was produced in the finalgaseous and liquid products during pyrolysis of the raw material, therewas 92% reduction in the presence of SO₂ in case of the treatedmaterial. Additionally, the production of liquid hydrocarbons appears tobe decreased by more than 80% in case of the treated sample while theprimary end product is a gas mixture rich in H₂, CO, CH₄, and otherhydrocarbons.

EXAMPLE 5

Used car tires are treated at elevated pressure using the reactor shownin FIG. 1 utilizing calcium nitrate as solvent. Since this material doesnot contain a large proportion of silicon in the ash, the pretreatmentis focused on the removal of alkali metals, phosphorus, chlorine,sulfur, as well as the deactivation of components remaining in thematerial structure after the end of the process by means of appropriatesalts so that they will be no longer a problem for the furtherthermochemical treatment of the treated material. The applied conditionsare the following: temperature 147° C., pressure 5-7 atm, solid/liquidratio 20% w/w dry basis, leaching time 7.5 minutes, solventconcentration 3% w/w, material particle size <3 mm. After thepretreatment, the sample is dried at 50° C. After the pretreatment, 2.1%weight increase of the treated dry material is noticed because of thecalcium absorption by the material. Sample analysis by electronmicroscopy SEM-EDX confirms the significantly increased calciumconcentration in the sample as well as the absence of chlorine andalkali metals while the sulfur concentration appears to be significantlyreduced by 17-35%. Then both the untreated and the treated material areused in fast pyrolysis tests (t=2 sec) at 600° C. and 800° C. Thesetests showed that the material conversion into gaseous and liquidproducts was increased from 37 to 75% at 600° C. and from 73 to 93.5% at800° C. after pretreatment. At the same time, although SO₂ was producedin the final gaseous and liquid products during pyrolysis of the rawmaterial, there was no presence of SO₂ in case of the treated material.Additionally, the production of liquid hydrocarbons appears to bedecreased by more than 80% in case of the treated sample while theprimary end product is a gas mixture rich in H₂, CO, CH₄, and otherhydrocarbons.

TABLE 1 Ash analysis and characterization of biomass, coal PretreatedPretreated Pretreated Pretreated Analysis Wheat Wheat Olive Olive CoalCoal Coal Coal (%) Straw Straw Kernel Kernel (HSMc) (HSMc) (EBWM) (EBWM)Ash 8.34 5.6 4.3 2.5 8.58 6.4 15.12 10.3 Content *K₂O 1.31 0.2 1.22 0.160.14 0.03 0.45 0.04 *Na₂O 0.56 0.09 0.03 0.02 0.07 0.02 0.12 0.019 SiO₂5 1 0.57 0.07 3.38 0.83 6.8 0.78 CaO 0.39 2.9 0.97 1.7 0.23 3.6 0.74 5.7P₂O₅ 0.35 0.05 0.2 0.05 nd nd nd nd SO₃ 0.13 0.02 0.05 0.03 0.35 0.10.73 0.21 Cl 0.13 0.00 0.12 0.00 0.047 0.00 0.15 0.00 Analysis (ppm) Cdnd nd nd Nd 0.38 0.039 1.2 0.12 As nd nd nd Nd 5.7 0.95 5.98 0.32 Ni ndnd nd Nd 31.9 2.15 33.86 1.55 Hg nd nd nd Nd 0.2 0.04 0.17 0.04 Zn nd ndnd Nd 34.18 4.76 55.78 2.59 Pb nd nd nd Nd 155.7 1.32 9.96 0.71 Cr nd ndnd Nd 11.77 4.01 27.89 2.18 Cu nd nd nd Nd 81.66 2.88 41.83 1.47 nd: notdetected, *non reactive forms in the case of the pretreated sample

TABLE 2 Thermal behavior of ash from raw and pretreated biomass typesand coal Ash samples Melting point (° C.) Raw olive kernel 850Pretreated olive kernel 1450 Raw wheat straw 800 Pretreated wheat straw1550 Raw coal (HSMc) 1300 Pretreated coal (HSMc) 1450 Raw coal (EBWM)1300 Pretreated coal (EBWM) 1450

1. Method for removing inorganic components (Si, K, Na, Cl, S, P, andheavy metals such as zinc, mercury, copper, lead, chromium, etc.) fromraw material for the production of clean and upgraded materials, wherethe raw material is biomass or coal or garbage or waste or sludges ormixtures of them, during which the process is performed in a first stageby leaching of the raw material with an aqueous solution containingstrong alkaline agents such as potassium, sodium bases, and/or theirsalts, followed in a second phase by washing the feedstock with anaqueous solution containing inorganic and/or organic salts containingone or more of the following cations of calcium, magnesium, ammonium,aluminum, titanium, zirconium and yttrium, and where the reactions takeplace under pressure and at elevated temperatures over 100° C.
 2. Methodaccording to claim 1, where the leaching of the raw material takes placeonly with aqueous solution containing organic and/or inorganic salts ofcalcium, magnesium, ammonium, aluminum, titanium, zirconium and yttrium,when the silicon concentration in the ash of the treated material isless than 10% and consequently silicon removal from the treated materialis not required.
 3. Method according to one of claim 1 or 2, where theleaching of the raw material in the second process step is done with anaqueous solution containing organic and/or inorganic salts and organicand/or inorganic acids.
 4. Method according to one of claim 1 or 2, and3 where the process is carried out under pressure in two steps using thereactor of FIG.
 1. 5. Method according to claim 4 where the process iscarried out under pressure at one stage, when the silicon removal fromthe material is not necessary, using the reactor of FIG.
 1. 6. Methodaccording to one of claim 1 or 2, 3 and 4 where the concentration ofstrong basic agents for silicon removal ranges from 0.5-1.5% weightbasis.
 7. Method according to one of claim 1 or 2, 3 and 4 where theconcentration of the salts and/or the salt/acid mixtures for the removalof alkali metals, chlorine, sulfur, phosphorus, heavy metals andnitrogen ranges from 0.5-4% weight basis.
 8. Method according to one ofclaims 1 to 7, where the conditions during which the treatment iscarried out in the first stage is temperature 110-150° C. and pressure2-atm if the material is biomass while temperature 130-195° C. andpressure 4-20 atm if the treated material is coal, garbage/waste forless than 5 minutes in case of biomass and less than 20 minutes in caseof coal, garbage/waste.
 9. Method according to one of claims 1 to 7,where the conditions during which the treatment is carried out in thesecond stage is temperature 110-160° C. and pressure 2-10 atm if thetreated material is biomass, temperature 140-195° C. and pressure 4-20atm if the treated material is coal, garbage/waste while pressure 4-45atm and temperature (140-245° C.) in case of plastics/polymer materialsespecially when they contain structural chlorine, for less than 5minutes in case of biomass and less than 20 minutes in case of coal,garbage/waste and plastic/polymer materials.
 10. Method according to oneof claims 1 to 9 where all water-soluble organic/inorganic salts ofcalcium, magnesium, titanium, zirconium, yttrium, aluminum and ammoniumin proportions of 0.07% up to 4% weight basis of the aqueous solutionare used as organic and/or inorganic compounds according to the type ofthe treated material.
 11. Method according to one of claims 1 to 9 wherein case of biomass, the solvent concentration is limited below 1.5%,while in case of coal and garbage/waste ranges from 0.5-4%.
 12. Methodaccording to one of claims 1 to 9 where both organic and inorganicacid/salt mixtures are used in the second step of the process to achievethe desired result considering that the proportion of acid is limited toless than 30% of the total mixture weight basis and preferably theextent of which does not lead to the creation of acidic conditionshaving a pH less than 5 in the pressurized solution.
 13. Methodaccording to one of claims 1 to 12, where the production of the aqueoussolution takes place with water regardless its origin, while leaching iscarried out at raw material/aqueous solution ratio from 15 grams perliter to 800 grams per liter.
 14. Method according to one of claims 1 to13, where leaching is carried out at raw material/aqueous solution ratiofrom 15 grams per liter to 400 grams per liter, temperature from 110° C.up to 245° C., and pressure from 2 atm to 45 atm during both stages oftreatment depending on the material treated, while the leaching timeranges from 2.5 minutes to 20 minutes.
 15. Method according to claim 14,where leaching is carried out at temperatures ranging from 110° C. to150° C., in each stage, while the leaching time ranges from 2.5 minutesto 4.99 minutes when the treated material is biomass.
 16. Methodaccording to claim 13, where leaching is carried out at temperaturesranging from 130° C. to 195° C., in each stage, while the leaching timeranges from 5 minutes to 20 minutes when the treated material is coal,garbage/waste.
 17. Method according to claim 13, where leaching iscarried out at temperatures ranging from 140° C. to 245° C., in eachstage, while the leaching time ranges from 5 minutes to 20 minutes whenthe treated material is a plastic/polymer material.
 18. Method accordingto one of claims 1 to 17, where the raw material consists of particlesand where the particle size ranges from a few micrometers to 5millimeters.
 19. Method according to one of claims 1 to 17, where theraw material consists of particles and where the particle size is lessthan 2 millimeters.
 20. Method according to claims 1 to 17 where theaqueous residue remaining after separation of the alkali compounds usedto create the aqueous solvent for the pretreatment of various materialsin step 1 of the treatment process is rich in silicon and is utilizedfor the production of pure silicon.
 21. Method according to claims 1 to17 where the aqueous residue remaining after separation of the organicand/or inorganic compounds used to create the aqueous solvent for thepretreatment of various materials in step 2 of the pretreatment processis rich in alkali metals, chlorine, sulfur and phosphorus and isutilized as high quality fertilizer.
 22. Method according to claims 1 to17 where the high pressure reactor consists of two separate reactors ina parallel mode. Each reactor contains an initial pressure vessel whereinitially the treated material and the aqueous solution are mixed underatmospheric conditions and ambient temperature with material/aqueousphase ratio from 15 grams per liter to 800 grams per liter and solventconcentration range between 0.5-1.5% weight basis depending on thematerial used.
 23. Method according to claims 1 to 17 and 22 where thematerial is treated during the first reaction stage in the firstpressurized compartment of the reactor with an aqueous alkali solution(base and/or salt), sodium, potassium, at temperature range of 110-150°C. and pressure 2-10 atm when the treated material is biomass whiletemperature 130-195° C. and pressure 4-20 atm when the treated materialis coal, garbage/waste for less than 5 minutes in case of biomass andless than 20 minutes in case of coal, garbage/waste.
 24. Methodaccording to claims 1 to 17, 22 and 23 where each pressure vesselaccording to FIG. 1 is equipped with a direct discharge valve whichcommunicates with the interior of the reactor via a pipeline at the endof which there is a 40 micron diameter solids filter. The immediatedepressurization caused by the discharge valve opening after the end ofthe treatment process results in solid/liquid separation letting theliquid to be concentrated and cooled in the recover tank before beingrecycled into the process as shown in FIG. 1 while the solid product isremoved in the second phase and is transferred to the second pressurizedvessel by opening the valve of the pressurized reactor's bottom. 25.Method according to claims 1 to 17, 22, 23 and 24 where the parallelreactor operates one step back from the initial reactor in order torealize a process which is semi-batch but in progress at any time. 26.Method according to claims 1 to 17, 22, 23, 24 and 25 where the secondcompartment of the pressurized reactor is used for the secondpretreatment stage by washing the material with an aqueous solution ofinorganic and/or organic salts.
 27. Method according to claims 1 to 17,22, 23, 24, 25 and 26 where the conditions in the second compartment ofthe reactor is temperature between 110-160° C. and pressure 2-10 atm ifthe treated material is biomass, temperature between 140-195° C. andpressure 4-20 atm if the treated material is coal, garbage/waste andpressure 4-45 atm and temperature between 140-245° C. in case ofplastics/polymer materials especially when they contain structuralchlorine, for less than 5 minutes in case of biomass and less than 20minutes in case of coal, garbage/waste as well as plastic/polymermaterials.
 28. Method according to claims 1 to 17, 22, 23 and 24 where80-99% of the silicon is removed from the ash of the treated materialduring the first leaching stage.
 29. Method according to claims 1 to 17,22, 23, 25, 26 and 27 where the calcium and/or magnesium and/or aluminumand/or titanium and/or zirconium and/or yttrium, and/or ammonium ionsare absorbed in the structure of the treated material in the secondprocess step.
 30. Method according to claims 1 to 16, where the nitrogenin the treated material which consists of biomass and/or coal and/orgarbage/waste is removed in the second leaching stage.
 31. Methodaccording to claims 1 to 17 where leaching is carried out by applyingelevated pressures and temperatures using commercially availablereactors operating at high pressures 2-30 atm and temperatures 110-350°C.
 32. Method according to claim 1, where the raw material is biomass orcoal or garbage or waste or sludges or mixtures of them, during whichthe leaching of the raw material with an aqueous solution containingstrong alkali agents such as strong bases and/or their salts isperformed in a first stage, followed in a second stage by washing of thefeedstock with an aqueous solution containing inorganic and/or organicsalts containing one or more of the following cations: calcium,magnesium, ammonium, aluminum, titanium, zirconium and yttrium, wherethe reactions take place in two steps under pressure 2-200 atm andelevated temperatures 110-345° C. using suitable high pressure reactors.The process involves the silicon removal from the ash of the treatedmaterial during the first leaching stage, and the incorporation ofcalcium and/or magnesium and/or aluminum and/or titanium and/orzirconium and/or yttrium and/or ammonium ions in the structure of thetreated material in the second process step realizing the simultaneousremoval of chlorine, alkali metals, sulfur, phosphorus, heavy metals,and nitrogen from the treated material.